(LAKE CO.) - A Chicago woman died Saturday morning when she fell off a motorcycle she was a passenger on while traveling on I-80/94.

Preliminary investigation by Master Trooper Russell Hayes revealed at approximately 9:42 a.m., this Saturday, May 07, 2016, morning a 1994 Harley Davidson motorcycle, driven by Rickey Salazar of Evergreen Park, Illinois was west bound on I-80/94 at the 8.2 mile marker (this is west of Grant Street) in the right lane when his passenger, Isela Vargas, 48 of Chicago, Illinois, for unknown reasons fell off the motorcycle.

Vargas sustained a serious head injury and was transported to North Lake Methodist Hospital in Gary where she was later pronounced dead. Vargas was not wearing a helmet. There was no damage to the motorcycle and Salazar was not injured.